Method for inhibiting cyclooxygenase and inflammation using cherry bioflavonoids

ABSTRACT

A method for inhibiting cyclooxygenase enzymes and inflammation in a mammal using a cherry or cherry anthocyanins, bioflavonoids and phenolics is described. In particular a mixture including the anthocyanins, the bioflavonoids and the phenolics is described for this use.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Ser. No. 09/317,310,filed May 24, 1999. This application is based upon Provisionalapplication Ser. No. 60/111,945, filed Dec. 11, 1998. This applicationis also based upon U.S. Provisional Application Ser. No. 60/120,178,filed Feb. 16, 1999.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

None

BACKGROUND OF THE INVENTION

1. Summary of the Invention

The present invention relates to a method of use of at least onecompound isolated from cherries as cyclooxygenase (COX-1 and COX-2)inhibitors. In particular, the present invention provides a naturalcherry composition containing a mixture of anthocyanins, bioflavonoidsand phenolics for use as anti-inflammatory agents as a result ofinhibition of the cyclooxygenase enzymes.

2. Description of Related Art

Many plant-derived compounds may also impart important positivepharmacological or “nutraceutical/phytoceutical” traits to foods by wayof their abilities to serve as antioxidants by maintaining low levels ofreactive oxygen intermediates, as anti-inflammatory agents by inhibitingprostaglandin synthesis, or as inhibitors of enzymes involved in cellproliferation. These activities may be important in ameliorating chronicdiseases including cancer, arthritis, and cardiovascular disease(Kinsella et al., Food Tech. 85-89 (1993). Thus, with natural products,the dietary supplement/food industry and neutraceutical/phytoceuticalcompanies have the opportunity to employ compounds which can not onlyenhance food stability as effectively as synthetic antioxidants, but canalso offer significant health benefits to the consumer.

Cherries are thought to have beneficial health properties in general.Consumption of cherries was reported to alleviate arthritic pain andgout (Hamel, P. B., et al. Cherokee Plants 28: Herald: Raleigh, N. C.(1975)) although there is no evidence for its active components or modeof action. These beneficial effects may be partially associated with theabundance of anthocyanins, the glycosides of cyanidin.

Prunus Cerasus L. (Rosacease), cv. MONTMORENCY is the major tart cherrycommercially grown in the United States. In order to challenge theMONTMORENCY monoculture, a new cultivar, BALATON tart cherry(Ujferbertoi furtos), was introduced into the United States in 1984, andhas been tested in Michigan, Utah, and Wisconsin. BALATON producesfruits darker than MONTMORENCY.

Colorants like anthocyanins have been regarded as the index of qualityin tart cherries. Most importantly, recent results showed thatanthocyanins such as cyanidin-3-glucoside have strong antioxidantactivities (Tsuda, T., et al, J. Agric. Food Chem. 42:2407-2410 (1994)).

Early studies have showed that MONTMORENCY cherry contains theanthocyanins cyanidin-3-gentiobioside and cyanidin-3-rutinoside (Li, K.C., et al., J. Am. Chem. Soc. 78:979-980 (1956)).Cyanidin-3-glucosylrutinoside was also found in six out of the sevensour cherry varieties (Harborne, J. B., et al., Phytochemistry 3:453-463(1964)). Dekazos (Dekazos, E. D., J. Food Sci. 35:237-241 (1970))reported anthocyanin pigments in MONTMORENCY cherry aspeonidin-3-rutinoside peonidin and cyanidin along withcyanidin-3-sophoroside, cyanidin-3-rutinoside and cyanidin-3-glucoside.However, cyanidin-3-glucosylrutinoside as well as cyanidin-3-glucoside,cyanidin-3-sophoroside and cyanidin-3-rutinoside were identified as mainpigments in sour cherries. Using HPLC retention values, Chandra et al(Chandra, A., et al., J. Agric. Food Chem. 40:967-969 (1992)) reportedthat cyanidin-3-sophoroside and cyanidin-3-glucoside were the major andminor anthocyanins, respectively, in Michigan grown MONTMORENCY cherry.Similarly, cyanidin-3-xylosylrutinoside was detected as a minor pigmentin MONTMORENCY cherry (Shrikhande, A. J. and F. J. Francis, J. Food Sci.38:649-651 (1973)).

In the prior art, production of pure anthocyanins (compounds 1-3 ofFIG. 1) from BALATON and MONTMORENCY cherry juices was carried out firstby adsorbing the pigment on an AMBERLITE XAD-2 (Sigma Chemicals) column(Chandra, A., et al., J. Agric. Food Chem. 41:1062-1065 (1993)). Thecolumn was washed with water until the eluant gave a pH of approximately7.0. The adsorbed pigments along with other phenolics were eluted withMeOH. The resulting crude anthocyanins were fractionated and purified byC-18 MPLC and HPLC, respectively, to afford pure anthocyanins forspectral studies. Purification of 500 mg crude MONTMORENCY anthocyaninsfrom AMBERLITE XAD-2 yielded 60 mg of pure anthocyanins 1-3 compared to391.43 mg from BALATON. This research indicated that crude anthocyaninsfrom MONTMORENCY obtained from the XAD-2 contained a high percentage ofother organic compounds. There was no attempt to use the crude mixtureof phenolics and anthocyanins for any purpose. U.S. Pat. Nos., 5,266,685to Garbutt, 5,665,783 to Katzakian et al and 5,817,354 to Mozaffardescribe various adsorbent resins and their use for isolating unrelatedproducts. These patents are only illustrative of the general state ofthe art in the use of adsorbent resins.

Cyclooxygenase (COX) or prostaglandin endoperoxide H synthase (PGHS-1,PGHS-2 or COX-1/COX-2) enzymes are widely used to measure theanti-inflammatory effects of plant products (Bayer, T., et al.,Phytochemistry 28 2373-2378 (1989); and Goda, Y., et al., Chem. Pharm.Bull. 40 2452-2457 (1992)). COX enzyme is the pharmacological targetsite for the nonsteroidal anti-inflammatory drug discovery (Humes, J.L., et al., Proc. Natl. Acad. Sci. U.S.A. 78 2053-2056 (1981); and Rome,L. H., et al., Proc. Natl. Acad. Sci. U.S.A. 72 4863-4865 (1975)). Twoisozymes of cyclooxygenase involved in prostaglandin synthesis arecyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2), respectively(Hemler, M., et al., J. Biol. Chem. 25 251, 5575-5579 (1976)). It ishypothesized that selective COX-2 inhibitors are mainly responsible foranti-inflammatory activity (Masferrer, J. L., et al., Proc. Natl. Acad.Sci. U.S.A. 91 3228-3232 (1994)). Flavonoids are now being investigatedas anti-inflammatory substances as well as their structural features forcyclooxygenase (COX) activity. The 5,7-dihydroxyflavone, galangin withan IC₅₀ of 5.5 μM, was found to be the most active cyclooxygenaseinhibitory flavonoid (Wurm, G., et al., Deutche Apotheker Zeitung 1222062-2068 (1982)). Flavonoids with an ortho-dihydroxy in ring A or Bwere stronger inhibitors than those with a free 3-OH group (Wurm, G., etal., Deutche Apotheker Zeitung 122 2062-2068 (1982); and Baumann, J., etal., Prostaglandins 20 627-640 (1980)). The C₂-C₃ double bond, whichdetermines the coplanarity of the hetero rings appears to be a majordeterminant of COX activity (Wurm, G., et al., Deutche Apotheker Zeitung122 2062-2068 (1982)). Certain prenylated flavonoids, such as morusin,were also active, because of their higher lipophilicity (Kimura, Y., etal., Chem. Pharm. Bull. 34 1223-1227 (1986)). Also, unsubstitutedflavone is a good COX inhibitor (Mower, R. L., et al., Biochem.Pharmacol. 33 357-364 (1984); and Welton, A. F., et al., Prog. Clin.Biol. Res. 213 231-242 (1986)). Most of the flavanones studied in thepast did not show significant COX inhibition, except for theflavanone-3-ol, silibinin (Kalkbrenner, F., et al., Pharmacology 44 1-12(1992)). However, the structure-activity relationships of isoflavonoidsare not reported.

There is a need for natural product derived compositions for use ascyclooxygenase inhibitors and as anti-inflammatory agents.

SUMMARY OF THE INVENTION

The present invention relates to a method for inhibiting cyclooxygenaseor prostaglandin H synthase enzymes which comprises: providing at leastone compound isolatable from a cherry with at least one of the enzymesto inhibit the enzymes.

Further, the present invention relates to a method for inhibitingcyclooxygenase or prostaglandin H synthase enzymes which comprises:providing at least one bioflavonoid compound isolatable from a cherrywith at least one of the enzymes to inhibit the enzymes.

Further, the present invention relates to a method for inhibitinginflammation in a mammal which comprises: administering at least onecompound isolatable from a cherry to the mammal to inhibit inflammation.

Further, the present invention relates to a method for inhibitinginflammation in a mammal which comprises: administering at least onebioflavonoid, anthocyanin or phenolic compound isolated from a cherry tothe mammal to inhibit the inflammation.

Finally, the present invention relates to a method for inhibitinginflammation in a mammal which comprises administering cyanidin to themammal to inhibit inflammation.

The term “anthocyanins” includes the color producing compounds containedin cherries. For the purpose of this application this incudes theaglycone cyanidin.

The term “bioflavonoids” means the isoflavonoid and flavonoid compoundscontained in cherries.

The term “phenolics” refers to compounds with a phenyl group and havingone or more hydroxyl groups.

The compounds isolated from cherries are most useful with livingmaterial. The living material can be in an animal or human. It can alsobe in tissue culture.

OBJECTS

It is therefore an object of the present invention to provide a cherrycompound which can be used as cyclooxygenase inhibitors andanti-inflammatory agents. Further, it is an object of the presentinvention to provide a method for isolating the composition on acommercial scale. Finally, it is an object of the present invention toprovide a natural source compound which is economical to prepare andeasy to use. These and other objects will become increasingly apparentby reference to the following description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the structure of the isolated anthocyanins (colorants) fromBALATON and MONTMORENCY cherries. The aglycon cyanidin has a hydroxylgroup at position 3.

FIGS. 2 and 3 are drawings showing the major bioflavonoids isolated fromthe cherries.

FIG. 4 shows the phenolics isolated from tart cherries.

FIG. 5 shows the steps in the method of producing the preferred isolateas described in Examples 1 and 2.

FIG. 6 is a schematic drawing showing the use of an open vessel 10 forholding resin beads, which remove anthocyanins, bioflavonoids andphenolics from the cherry juice.

FIG. 7 is a dose-response curve for the inhibition of the human PGHS-1enzyme by cyanidin. The antiinflammatory activity of cyanidin wasestimated by its ability to inhibit the cyclooxygenase activity of thePGHS-1 enzyme. Cyanidin gave an IC₅₀ value of 90 μM for PGHS-1 enzyme,while the NSAID aspirin, naproxen, and ibuprofen gave IC₅₀ values of1050, 11, and 25 μM, respectively.

FIG. 8 is a dose-response curve for the inhibition of PGHS-1 and PGHS-2enzymes by cyanidin. Cyanidin gave IC₅₀ values of 90 and 60 mM forPGHS-1 and PGHS-2 enzymes, respectively.

FIG. 9 is a graph showing the inhibitory effect of PGHS-1 (COX-1) byflavonoids and isoflavonoids at 200 μm concentrations. Data is expressedas mean ±S.E. of triplicate. Kaempferol 3-rutinoside, 3′-methoxykaempferol 3-rutinoside, 5,8,4′-trihydroxy-6,7-dimethoxyflavone andquercetin were not active at 1000 μM concentrations.

FIG. 10 is a graph showing dose response curves for the inhibition ofthe PGHS-1 enzyme (COX-1) by flavonoids from BALATON tart cherriescompared to the non-steroidal anti-inflammatory drugs, naproxen,aspirin, and ibuprofen. The IC₅₀ of kaempferol, quercetin, luteolin,aspirin, naproxen and ibuprofen are 180, 350, 300, 1050, 11 and 25 μM,respectively. Data is expressed as mean ±S.E. of triplicate.

FIG. 11 are graphs showing dose response curve for the inhibition of thePGHS-1 enzyme (COX-1) by isoflavonoids from BALATON tart cherriescompared to the non-steroidal anti-inflammatory drugs, naproxen, aspirinand ibuprofen. The IC₅₀ of daidzein, biochanin A, genistein, aspirin,naproxen and ibuprofen are 400, 350, 80, 1050, 11 and 25 μM,respectively. Data is expressed as mean ±S.E. of triplicate.

DESCRIPTION OF PREFERRED EMBODIMENTS

The isolates are preferably prepared as a mixture of anthocyanins,bioflavonoids and phenolics by a method for producing a mixturecomprising anthocyanins, bioflavonoids and phenolics from cherries as acomposition which comprises:

(a) providing an aqueous solution containing the anthocyanins,bioflavonoids and phenolics from the cherries;

(b) removing the anthocyanins, bioflavonoids and phenolics onto a resinsurface from the aqueous solution;

(c) eluting the resin surface with an eluant to remove the anthocyanins,bioflavonoids and phenolics from the resin surface; and

(d) separating the eluant from the anthocyanins, bioflavonoids andphenolics.

The cherries used to produce the isolates can be sweet or sour. Tartcherries contain high levels of malic acid in addition to other organicacids which contributes to the sour taste of tart cherries. The methodisolates malic acid and other organic acids containing sugars which canbe used in foods to provide tartness and flavor. Most preferred are theBALATON and MONTMORENCY cherries.

The isolated mixture of anthocyanins, bioflavonoids and phenolics can betableted and used as a natural nutraceutical, phytoceutical or dietarysupplement. In general, the tablets provide a daily dose of theanthocyanins and bioflavonoids of about 1 to 200 mg, preferably a dailydose of 10-100 mg. One hundred (100) cherries provide 10 to 100 mg ofanthocyanins and bioflavonoids. The phenolics (FIG. 4) are provided inan amount of 0.1 to 100 mg as a daily dose. One hundred cherries provide1-50 mg of phenolics. The amount of the anthocyanins, bioflavonoids andphenolics can be adjusted by isolating the individual compounds andblending them together. It is preferred to use the natural mixture ofthe anthocyanins, bioflavonoids and phenolics which is isolated by themethod using the adsorbent resin.

The resin has a surface to which the anthocyanins, bioflavonoids and thephenolics are adsorbed. A preferred class of adsorptive resins arepolymeric crosslinked resins composed of styrene and divinylbenzene suchas, for example, the AMBERLITE series of resins, e.g., AMBERLITE XAD-4and AMBERLITE XAD-16, which are available commercially from Rohm & HaasCo., Philadelphia, Pa. Other polymeric crosslinked styrene anddivinylbenzene adsorptive resins suitable for use according to theinvention are XFS-4257, XFS-4022, XUS-40323 and XUS-40322 manufacturedby The Dow Chemical Company, Midland, Mich., and the like.

It is preferred to use commercially available, FDA-approved,styrene-divinyl-benzene (SDVB) cross-linked copolymer resin, (e.g.,AMBERLITE XAD-16). Thus, in the preferred embodiment, AMBERLITE XAD-16,commercially available from Rohm and Haas Company, and described in U.S.Pat. No. 4,297,220, herein incorporated by reference, is used as theresin. This resin is a non-ionic hydrophobic, cross-linked polystyrenedivinyl benzene adsorbent resin. AMBERLITE XAD-16 has a macroreticularstructure, with both a continuous polymer phase and a continuous porephase. In a particularly preferred embodiment, the resin used in thepresent invention has a particle size ranging from 100-200 microns.

It is contemplated that other adsorbents such as those in the AMBERLITEXAD adsorbent series which contain hydrophobic macroreticular resinbeads, with particle sizes in the range of 100-200 microns, will also beeffective in the methods of the present invention. Moreover, differentvariations of the AMBERLITES, such as the AMERCHROM CG series ofadsorbents, used with particle sizes in the range of 100-200 microns,may also be suitable for use in the present invention. The AMBERLITEXAD-16 is preferred since it can be re-used many times (over 100 times).However, it is contemplated that for food, the use ofgovernmentally-approved resins in the present invention will beconsidered important and/or desirable.

Any solvent can be used to remove the adsorbed anthocyanins,bioflavonoids and phenolics. Preferred are lower alkanols containing 1to 4 carbon atoms and most preferred is ethanol (ethyl alcohol) since itis approved for food use. Typically the ethanol is azeotroped withwater; however, absolute ethanol can be used. Water containing malicacid and sugars in the cherries pass through the column. These arecollected and can be used in foods as flavors.

The anthocyanins, bioflavonoids and phenolics are preferably isolatedfrom the BALATON and the MONTMORENCY cherries. The composition of thecherries is in part shown in part by U.S. application Ser. No.08/799,788 filed Feb. 12, 1997 and in part U.S. application Ser. No.60/111,945, filed Dec. 11, 1998 and 60/120,178, filed Feb. 16, 1999,which are incorporated by reference herein.

The term “carrier” or “bulking agent” is used to mean a compositionwhich is added to increase the volume of the composition of the purifiedcomposition from the cherry. Preferred is dried cherry pulp. Theseinclude any edible starch containing material, protein, such as non-fatdry milk. Within this group are flour, sugar, soybean meal, maltodextrinand various condiments, such as salt, pepper, spices and herbs, forinstance. The bulking agent is used in an amount between about 10⁻⁶ and10⁶ parts by weight of the mixture.

The ratio of anthocyanins, bioflavonoids and phenolics to the carrier isbetween 0.1 to 100 and 100 to 0.1.

The composition is introduced into the food in an amount between about0.1 and 10 mg/gm of the active ingredients of the food. The amount ispreferably selected so as to not affect the taste of the food and toproduce the most beneficial result. The food can be high (wet) or lowmoisture (dry) as is well known to those skilled in the art. When usedas a dietary supplement the tablets contain between 0.1 to 1 gram ofactive ingredient.

Methods have been developed for extraction and isolation ofphytochemicals (Chandra, A., et al., J. Agric. Food Chem. 41:1062(1992); Wang, H., et al., J. Agric. Food Chem. 45:2556-2560 (1997)) andfor rapid screening of antioxidant activity (Arora, A. and G. M.Strasburg, J. Amer. Oil Chem. Soc. 74:1031-1040 (1997)). These methodsare being utilized to identify, characterize and test the compounds fromBALATON and MONTMORENCY cherries. Juiced cherry tissue was sequentiallyextracted with hexane, ethyl acetate and methanol. Both methanol andethyl acetate fractions showed strong antioxidant activity in thescreening assay. The ethyl acetate fraction was further purified bysilica gel vacuum liquid chromatography to yield four subfractions; thesubfraction was further separated into seven fractions by preparativereverse phase HPLC. FIGS. 2 and 3 show the bioflavonoids isolated fromthe BALATON cherries. There are thus numerous analogous or homologouscompounds in the tart cherries. The anthocyanin components obtained fromthe juice fraction also have been identified and fully characterized(Chandra, A., et al., J. Agric. Food Chem. 41:1062 (1992); Wang, H., etal., J. Agric. Food Chem. 45:2556-2560 (1997)).

Two novel phenolic compounds were identified:

I) 1-(3′-4′-dihydroxy cinnamoyl)-2,3-dihydroxy cyclopentane, and II) 1-(3′-4′-dihydroxy cinnamoyl) -2,5-dihydroxy cyclopentane. Other compoundsisolated from the ethyl acetate extract of cherry fruits andcharacterized by spectral methods include: 1-(3′-methoxy, 4′-hydroxycinnamoyl) quinic acid, 2-hydroxy-3-(2′-hydroxyphenyl) propanoic acid,methyl 2-hydroxy-3-(2′-hydroxyphenyl) propanoate, D(+)-malic acid,β-sitosterol ad β-sitosterol glucoside. FIG. 4 shows some of thephenolics which were isolated.

EXAMPLES 1 and 2

As shown in FIG. 5, individual quick frozen (IQF) cherries (which hadbeen pitted) were defrosted and blended in an industrial WARING blender.The mixture was centrifuged at 10,000 rpm and the juice was decanted.The residue, pulp, was further pressed with cheese cloth to remove anyadditional juice.

The pulp was lyophilized at 15° C. The juice was processed on AMBERLITEXAD-16 HP resin to produce cherry sour, anthocyanins, bioflavonoids andphenolics. The XAD-16 resin, 1 kg, was washed with ethanol (1-2 L) andthen washed with water (6 L). The XAD-16 resin was allowed to stand inwater for 1 hour before loading into a glass column (10 ID×90 cm long)with a cotton plug. The packed column was washed with water (2 L) beforeloading the juice for separation. 800 mL juice was purified each time.The juice was added onto the surface of the column and allowed to settlewith no flow. It was then eluted with water and the first 1 L wasdiscarded. The next 2 L of washing was collected, since it contained thecherry juice which was sour since it contained malic acid and sugarsfrom the cherries. The column was then washed with an additional 4 L ofwater in the case of BALATON and 5 L for MONTMORENCY cherry juice. Oncethe cherry juice was collected, the remainder of the washing with waterwere discarded. The column was then eluted with ethanol (1.3-1.5 L) andcollected the red solution containing anthocyanins, bioflavonoids andphenolics (700-800 ml). The column was then run dry and washed with 10 Lof water before repeating the process many of times (over 100).

The red alcoholic solution was then evaporated under vacuum a (20millitorr) to remove ethanol and the aqueous solution, stabilized with50 ppm ascorbic acid, was lyophilized at 10° C. The red powder wascollected and stored.

Example 1 results:

BALATON cherry Weight of IQF cherries 15.74 kg Weight of dried pulp 605g Volume of juice 12.16 L Weight of anthocyanins, bioflavonoids 31.35 gand phenolics (red powder) Volume of sour byproduct @ 35 L (malic acidand sugars)

Example 2 results:

MONTMORENCY cherry Weight of IQF cherries 30.45 kg Weight of dried pulp895 g Volume of juice 24.03 L Weight of anthocyanins, bioflavonoids and47 g phenolics (red powder) Volume of cherry by-product @ 75 L (malicacid and sugars)

The red powders of Examples 1 and 2 were preferably mixed with driedpulp as a carrier and tableted into 1 to 1000 mg tablets including thecarrier (1 adult daily dose).

Various food grade acids can be added to the isolated anthocyanins,bioflavonoids and phenolics to prevent decomposition. Preferably they donot add flavor. Ascorbic acid (vitamin C) is preferred. The acid can beadded before or after, preferably before drying of the cherry compounds.

For small scale processing, lyophilization is used to remove water. Forlarger scale production, drying in an air circulating oven is preferred.

EXAMPLE 3

As shown in FIG. 6, an open vessel 10 is provided with an inlet line 11and an outlet line 12, with valves 13 and 14, respectively. The resinbeads 15 are provided in the open vessel 10. Water is introduced intothe vessel 10 and then removed through outlet line 12 and discarded. Thecherry juice (without the pulp or pits) as in Example 1 is introduced tothe vessel 10 and allowed to stand for 25 minutes. The temperature ofthe water and juice is between about 20 and 30° C. The cherry juiceresidue containing malic acid and sugars is then removed through theoutlet line 12 and retained as a food flavoring. The resin 15 in thevessel is then washed again with water from inlet line 11 and thenremoved and discarded through outlet line 12. The anthocyanins,bioflavonoids and phenolics on the resin particles are then extractedusing 95% ethanol introduced through inlet line 11. The ethanolcontaining the anthocyanins, bioflavonoids and phenolics is removed fromthe vessel 10. The ethanol is removed from the anthocyanins,bioflavonoids and phenolics and dried using flash drying under nitrogen.The resulting powder is preferably then mixed with dried cherry pulp orother carrier as in Example 1. The resin particles are washed with waterand then the resins and ethanol are recycled many times.

EXAMPLE 4

The antiinflammatory assays on the anthocyanins and cyanidin wereconducted using prostaglandin endoperoxide H synthase-1 and -2 isozymes(PGHS-1, and -2) and were based on their ability to convert arachidonicacid to prostaglandins (PGs). The positive controls used in thisexperiment were aspirin, naproxen, and ibuprofen. Aspirin gave an IC₅₀value of 1050 μM each against PGHS-1 and PGHS-2 enzymes (FIG. 7).Naproxen and ibuprofen gave IC₅₀ values of 11 and 25 nM against PGHS-1enzyme, respectively (FIG. 7). A preliminary experiment with the mixturecontaining anthocyanins 1-3 (FIG. 1) showed PGHS-1 and PGHS-2 activitiesat 33 ppm concentration. The aglycon cyanidin showed good PGHS-1 and -2inhibitory activities, with IC₅₀ values of 90 and 60 nM, respectively(FIGS. 7 and 8). The ratio of IC₅₀ values for PGHS-1 to PGHS-2 was about0.56 (FIG. 8). However, pure anthocyanins 1-3 showed little or noactivity against PGHS-1 and PGHS-2 at 300-nM test concentrations. Higherconcentrations of anthocyanins 1 and 2, on the contrary, increased theactivity of enzyme. This is probably due to the ability of anthocyanins1 and 2 to act as oxygen carriers at high concentration and enhance theoxygen uptake. It is noted that anthocyanins are hydrolyzed in the gutof a mammal to cyanidin and other compounds and thus effective in vivo.

For measurements of time-dependent inhibition of PGHS-2 enzyme activityby cyanidin, the enzyme was preincubated at 37° C. with 15 nM ofcyanidin (one-fourth of the concentration of IC₅₀) and added to anoxygen electrode chamber with arachidonic acid substrate to initiate thereaction. The results suggest that the rate of inhibition of PGHS-2 didnot change with time.

The specific inhibition of the PGHS-2 enzyme is a major advance inantiinflammatory therapy because it significantly reduces the adverseeffects of nonsteroidal antiinflammatory drugs (NSAIDs). It is generallybelieved that ulcerogenic and other adverse properties of NSAIDs resultfrom the inhibition of PGHS-1, whereas the therapeutically desirableeffects come from the inhibition of PGHS-2 enzyme.

Similarly, cyanidin showed better antiinflammatory activity than aspirinin the inflammatory assays. The antioxidant and antiinflammatoryproperties of anthocyanins and cyanidin suggest that consumption ofcherries may have the potential to reduce cardiovascular or chronicdiseases in humans.

In particular, arachidonic acid and a microsomal fraction of ram seminalvesicles containing PGHS-1 enzyme suspended in 100 mM Tris pH 7.8 and300 μM diethyldithiocarbamic acid (DDC) as a preservative were purchasedfrom Oxford Biomedical Research (Oxford, Mich.). Recombinant humanPGHS-2 enzyme was initially obtained from Dr. David Dewitt (Departmentof Biochemistry, Michigan State University, East Lansing, Mich.) andthen purchased from Oxford Biomedical Research (Oxford, Mich.).Naproxen, ibuprofen, and hemoglobin were purchased from Sigma ChemicalCo. (St. Louis, Mo.). Anthocyanins 1-3 were purified from Balaton tartcherry by HPLC and were identified by ¹H and ¹³C NMR spectral data.

To prepare cyanidin, the anthocyanin mixture containing 1-3 (FIG. 1; 500mg) was stirred with 3N HCl (20 mL) at 80° C. for 10 hours. The reactionmixture was purified on a XAD-4 column as in the preparation ofanthocyanins. The MeOH solution of cyanidin was evaporated to dryness toyield a red amorphous powder (190 mg) and stored at −30° C. until use.

In the antiinflammatory assay, cyclooxygenase activities were measuredby using PGHS-1 enzyme (ca. 5 mg protein/mL in 0.1 M TrisHCl, pH 7.8), ahomogeneous protein purified from ram seminal vesicles. Microsomalpreparations from recombinant human prostaglandin synthase-2 (COX-2)were obtained from insect cell lysate. Assays were performed at 37° C.by monitoring the initial rate of O₂ uptake using an O₂ electrode(Yellow Springs Instrument Inc., Yellow Springs, Ohio). Each assaymixture contained 3 mL of 0.1 M Tris HCl, pH adjusted to 7 by theaddition of 6M HCl, 1 mM phenol, 85 μg hemoglobin, and 10 μM ofarachidonic acid. Reactions were initiated by the addition of 5-25 μg ofmicrosomal protein in a volume of 15-50 μL. Instantaneous inhibition ofenzyme activity was determined by measuring the cyclooxygenase activityinitiated by adding aliquots of microsomal suspensions of PGHS-1 orPGHS-2 (10 μM O₂/min cyclooxygenase activity/aliquot) to assay mixturescontaining 10 μM arachidonate and various concentrations of the testsubstances (10-1100 μM). The IC₅₀ values represent the concentrations ofthe test compound that gave half-maximal activity under the standardassay conditions.

EXAMPLE 5

This is an antiinflammatory assay for cyclooxygenase inhibition activityof flavonoids and isoflavonoids. Arachidonic acid and microsomalsuspensions of PGHS-1 (COX-1) and COX-2 (PGHS-2) were purchased fromOxford Biomedical Research (Oxford, Mich., USA). Genistein, genistin,naringenin, quercetin, 5,8,4′-trihydroxy-6,7-dimethoxyflavone,kaempferol-3-rutinoside and 3′-methoxy kaempferol 3-rutinoside werepurified from BALATON tart cherry by HPLC and were identified by ¹H- and¹³C NMR spectral data. Daidzein and formononetin were purchased fromResearch Plus, Inc. (Bayonne, N.J., USA). Biochanin A, kaempferol,quercetin, naproxen, ibuprofen and hemoglobin were purchased from SigmaChemical Co. (St. Louis, Mo., USA). Luteolin was purchased from AdamsChemical Co. (Round Lake, Ill., USA).

For measuring the COX activity, flavonoids or isoflavonoids weredissolved in DMSO to yield 40 mM stock solution and was further dilutedto the desired concentration according to the COX-1/COX-2 inhibitoryactivity of each compound assayed.

Anti-inflammatory assay: COX activities were measured using microsomalsuspensions of PGHS-1 and PGHS-2. Microsomal membranes (5 mg protein/mLin 0.1 M Tris HCl, pH 7.4) were prepared and assayed on the same day.COX-1 and COX-2 assay was performed at 37° C. controlled by acirculation bath (Model-1166, VWR Scientific Products, Chicago, Ill.) bymonitoring the rate of O₂ uptake using a 5357 Oxygen electrode (INSTECHLaboratory, Plymouth Meeting, Pa.) (Meade, E. A., et al., J. Biol. Chem.268 6610-6614 (1993)).

Each assay mixture contained 600 μL of 0.1 M Tris-HCl, pH 8.0, 1 mMphenol, 17 μg hemoglobin and 10 μM arachidonate and were mixed in amicrochamber (INSTECH Laboratory, Plymouth Meeting, Pa., USA). Foranthocyanins and cyanidin pH 7 is preferred to prevent decomposition inabsence of additives. Reactions were initiated by adding 5 μg ofmicrosomal protein (5 μL). Instantaneous inhibition was determined bymeasuring the cyclooxygenase activity initiated by adding microsomalsuspensions of PGHS-1 or PGHS-2 in the assay mixtures containing 10 μMarachidonate and various concentrations of test compounds. The IC₅₀values represent the concentrations of inhibitor that gave half-maximalactivity under the standard assay conditions. The kinetics of the enzymeactivity was monitored by Biological Oxygen Monitor (YSI model 5300,Yellow Springs Instrument CO., Inc., Yellow Springs, Ohio) and collectedin Quicklog Data Acquisition and Control computer software (StrawberryTree Inc., Sunnyvale, Calif., USA).

The COX-1/COX-2 activity of BALATON cherry bioflavonoids was determinedby monitoring the O₂ uptake. Reactions were initiated by adding PGHSenzyme preparation. One unit of cyclooxygenase represents oxygenation of1 nmol of arachidonate/min under the standard assay condition by the COXenzyme. This assay was a modification of the assay reported by DeWitt etal. (Dewitt D. L., et al., J. Biol. Chem. 265 5192-5198 (1990)). 10 μMarachidonate has been used for COX-1 assays, because this substrateconcentration was reported to give near-maximal COX activity and alsopermit the detection of enzyme inhibition by lipophilic inhibitors(Meade, E. A., et al., Biol. Chem. 268 6610-6614 (1993)). Thismethodology can also be used for COX-2 assay as well using COX-2 enzyme.Three known COX inhibitors, aspirin, ibuprofen and naproxen, wereselected as positive controls. COX-1 inhibitory activities offlavonoids, kaempferol, quercetin, luteolin, quercetin 3-rhamnoside,5,8,4′-trihydroxy-6,7-dimethoxyflavone were compared. Kaempferol3-rutinoside, 3′-methoxy kaempferol 3-rutinoside and naringenin (FIG.9), and five isoflavonoids, genistein, genistin, daidzein, formononetinand biochanin A (FIG. 8).

COX-1/COX-2 inhibitory activities of each compound at differentconcentrations was calculated by comparing the tangent of O₂ uptakecurves of test compounds with that of blank control. Each assay wasrepeated 3 times and the IC₅₀ values (50 inhibitory concentrations) werecalculated by linear regression analysis. The half-maximal inhibitoryconcentrations of flavonoids and isoflavonoids are shown in FIG. 11.Dose response curves for the inhibition of the COX-1 enzyme byflavonoids and isoflavonoids from BALATON tart cherries compared to thenon-steroidal anti-inflammatory drugs, aspirin, naproxen and ibuprofenare shown in FIGS. 10 and 11, respectively.

Among the flavonoids tested, kaempferol showed the highest COX-1inhibition, followed by luteolin, quercetin, naringenin and quercetin3-rhamnoside (FIG. 9). In comparing kaempferol with quercetin, it wasfound that the presence of a hydroxyl group at C₃′ position decreasedthe COX-1 inhibitory activity (FIG. 9). The COX-1 inhibitory activity ofkaempferol and quercetin were reported in other model systems(Kalkbrenner, F., et al., Pharmacology 44 1-12 (1992); Hoult, J. R. S.,et al., Agents and Actions 42 787-792 (1988); and Moroney, M. A., etal., J. Pharm. Pharmacol. 40 787-792 (1988)). The OH group at C₃position is also important for the activity. However, the glycosylationof the OH group at C₃ decreased the activity considerably. Comparing theCOX-1 inhibitory activity of flavones (luteolin) with theircorresponding flavanols (quercetin), it can be concluded that theabsence of an OH group at C₃ enhanced the COX-1 activity slightly. It isimportant to note that quercetin 3-rhamnoside was not active in theassay, but reported to have in vivo anti-inflammatory activity (SanchezDe Medina, L. H., et al., J. Pharmacol. Exp. Ther. 278 771-779 (1996)).This may be due to the in vivo metabolism of quercetin 3-rhamnoside toquercetin. The C₂-C₃ double bond, which determines the coplanarity ofthe hetero-rings in flavonoids and isoflavonoids, was essential for ahigher COX inhibitory activity. If the double bond was saturated, theCOX-1 inhibitory effect was dramatically decreased as in the case ofnaringenin (FIG. 9). This result is consistent with previous reports(Wurm, G., et al., Deutche Apotheker Zeitung 122 2062-2068 (1982);Kalkbrenner, F., et al., Pharmacology 44 1-12 (1992)). Also, themultiple substituents such as OH and OMe groups in the A ring of theflavonoids caused little or no COX-1 inhibition as demonstrated by theactivity of 5,8,4--trihydroxy-6,7-dimethoxyflavone.

Among the isoflavonoids (FIGS. 2 and 3), genistein showed the highestCOX-1/COX-2 inhibitory activity. The activity was dramatically decreasedin genistin, when the 7-OH group in ring A of genistein wasglycosylated. Also, the hydroxyl group at C-4′ in isoflavonoids isessential for the COX-1/COX-2 inhibitory activity. When 4′-OH groups ingenistein and daidzein were methylated, the activity decreasedconsiderably. The 5-OH group in isoflavonoids is also important forCOX-1/COX-2 inhibitory effect. These results indicated that C₄′, C₅ andC₇ hydroxyl groups in isoflavonoids are essential for COX-1 inhibition.Comparison of genistein with that of kaempferol indicates thatsubstitutions on ring B and at C₃ of ring C enhances COX-1/COX-2inhibitory effect. In addition to COX-1/COX-2 inhibition, theseisoflavonoids and flavonoids also showed good antioxidant activity. BothCOX-1 inhibitory and antioxidant activities of these compounds suggeststhat tart cherries may possess significant health benefits to humans.These bioflavonoids may be partially responsible for the anecdotalclaims associated with tart cherries of alleviating pain related totreatment of arthritis and gout.

Thus several flavonoids and isoflavonoids isolated from BALATON tartcherry were assayed for prostaglandin H endoperoxide synthase (PGHS-1 orPGHS-2) enzyme activity. Genistein showed the highest COX-1 inhibitoryactivity among the isoflavonoids studied with an IC₅₀ value of 80 μM.Kaempferol gave the highest COX-1 inhibitory activity among theflavonoids tested with an IC₅₀ value of 180 μM. The structure-activityrelationships of flavonoids and isoflavonoids revealed that hydroxylgroups at C₄′, C₅ and C₇ in isoflavonoids were essential for appreciableCOX-1 inhibitory activity. Also, the C₂-C₃ double bond in flavonoids isimportant for COX-1 inhibitory activity. However, hydroxyl group at C₃′position decreased the COX-1/COX-2 inhibitory activity by flavonoids.

EXAMPLE 6

The composition of Examples 1 and 2 were tested for anti-inflammatoryactivity using cyclooxygenase 1 and 2 (COX-1 and COX-2) in an assay asdescribed in Wang et al., J. Nat. Products 62:294-296 (1999); Wang etal., J. of Ag. and Food Chemistry, 47: 840-844 (1999) and Wang et al.,J. of Nat. Products, 62:86-88 (1999) and Examples 4 and 5. The resultswere that the compositions exhibited anti-inflammatory activities,specifically strong inhibition of COX-1 and COX-2.

It is intended that the foregoing description be only illustrative ofthe present invention and that the present invention be limited only bythe hereinafter appended claims.

We claim:
 1. A method for inhibiting cyclooxygenase or prostaglandin Hsynthase enzymes comprising: providing at least one compound anthocyaninselected from the group consisting of cyanidin-3-glucosylrutinoside,cyanidin-3-rutinoside and or cyanidin-3-glucoside isolated from thefruit of a cherry to inhibit the enzymes.
 2. The method of claim 1wherein the method is in vitro.
 3. The method of claim 1 wherein themethod is in vivo.
 4. The method of any one of claims 1, 2 or 3 whereinthe compound is from a tart cherry.
 5. The method of any one of claims1, 2 or 3 wherein the compound is isolated from a sweet cherry.
 6. Amethod for inhibiting inflammation in a mammal comprising: administeringto a mammal in need of such treatment, an effective amount of at leastone anthocyanin obtained from the fruit of a cherry, said anthocyaninselected from the group consisting of cyanidin-3-glucosylrutinoside,cyanidin-3-rutinoside, and cyanidin-3-glucoside and mixtures thereof toinhibit said inflammation.
 7. The method of claim 6 wherein saidanthocyanin is obtained from Prunus avium, Prunus cerasus, and mixturesthereof.
 8. The method of claim 6 wherein said anthocyanin is obtainedfrom Prunus cerasus.